class Solution {
    public int uniquePaths(int m, int n) {
        int[][] arr = new int[m+1][n+1] ;
        arr[1][1] = 1 ;
        for(int i=1 ; i <= m ; i ++){
            for(int j= 1 ; j <= n ; j++){
                if(i==1&&j==1){
                   continue ;
                }
                arr[i][j] = arr[i][j-1] + arr[i-1][j];
            }
        }
        return arr[m][n];
    }
}